Tool revolver

ABSTRACT

The invention relates to a tool revolver, in particular for a machine tool, comprising a tool disk ( 1 ) which is rotatable about a revolver axis and provided with a plurality of tool stations which are distributed along the disk circumference and can be moved to an operation position by the disk ( 1 ) rotation, wherein at least one part of said tool stations ( 13 ) comprises a reception area ( 25 ) for receiving a tool holder ( 3 ) and a fixing device is used for fixing a corresponding tool holder ( 3 ) at a defined position in the reception area ( 25 ), respectively. The interaction between an elastic adjusting body ( 31 ) which is protruded perpendicularly to the reception area ( 25 ) and is used in the form of an orientation element for positioning, and adjusting surfaces ( 41, 43 ) deepened into a base surface ( 7 ) of the tool holder ( 3 ) enables the tool holder to take an adjustment position when a screw fitting is fastened.

The invention relates to a tool revolver, in particular for machine tools, having a tool disk which can turn around the revolver axis, and which has a plurality of tool stations which are distributed along its periphery and which can be set by turning the tool disk into at least one working position at a time, on at least some of the tool stations there being a receiver for a tool holder and one fastening means each being provided in order to fix the respective tool holder on the pertinent receiver in defined positioning.

Tool revolvers of this type are known, compare, for example, publication WO 93/23191. Due to the possibility of being able to position tool holders with various machining tools in rapid alternation by controlled rotation of the tool disk, these tool revolvers are advantageously used to a large extent in industrial engineering.

But the disadvantage in these tool revolvers is that when the machining tools are being changed, when the pertinent tool holders are to be mounted on the receiver of the tool disk, the tool holder on the receiver must be adjusted in order to align the machined workpiece to the desired position. For known tool revolvers of the aforementioned type, adjustment must be done using adjustment screws for each tool holder.

Proceeding from this prior art, the object of the invention is to make available a tool revolver in which it is ensured that the pertinent tool holders, when they are being fixed on the receiver of the tool disk by the fastening means, assume an exactly defined setting position.

According to the invention this object is achieved by a tool revolver which has the features of claim 1 in its entirety.

In that, as specified in the characterizing part of claim 1, the arrangement is such that for positioning as an alignment means there are at least one fitting body which projects out of the receiver and which is elastically resilient perpendicular to it, and fitting surfaces which are recessed in the base surface of the tool holder for interaction with at least one fitting body, it is ensured that the toolholder assumes the exact, desired setting position when the screws are tightened. Therefore the invention avoids the requirement of taking adjustment measures each time the tool holder is used.

In advantageous embodiments, the receiver on the respective tool stations is a plate which is connected to the tool disk and which with its flat surface which lies radially outside relative to the revolver axis borders contact surfaces of the tool disk on both sides, which surfaces extend in the plane parallel to the revolver axis and with which the respectively assignable tool holder with its base surface can be brought into contact. For bracing with the base surface of the tool holder to be attached, which surface is made to fit the respective contact surface in shape and dimension, a large-area, flat contact surface is therefore available; this promotes especially reliable fixing by means of screw joints.

In especially advantageous embodiments, on both ends of the plate on its longitudinal axis, there is one fitting body each so that alignment takes place advantageously at alignment sites which are spaced far apart.

The fitting bodies can have the shape of a prismatic body which is blunt on the top, away from its top to both sides of the longitudinal axis, flat fitting flanks diverging from one another extending down and defining planes which are parallel to the longitudinal axis of the plate.

In order to enable spring resilience of the fitting bodies, for which this elastic resilience at extremely high spring constants should take place with deflections which lie each only in the micron range, in the area underneath the fitting bodies there can be a slight clearance between the bottom of the plate and the facing surface of the tool disk.

The fitting surfaces of the respective tool holder which interact with the fitting bodies of the plate can be formed by inside surfaces of at least one groove which has been recessed in the base surface of the tool holder.

Preferably the respective groove in the base surface extends over a longitudinal area beyond the area of the respective fitting body, and the arrangement can be made such that for each fitting body there is a groove with inside surfaces which need not form flat surfaces. Rather it can be provided that the groove base and/or side surfaces is or are crowned such that the groove depth and/or groove width proceeding from its open end decreases inwardly.

Alternatively there can be a single groove which has flat fitting surfaces and which is made continuous in the base surface of the tool holder for the two fitting bodies.

The invention is explained in particular below using embodiments shown in the drawings.

FIG. 1 shows a perspective, detached, and exploded oblique view of a peripheral section of the tool disk of one embodiment of the tool revolver according to the invention, a tool holder being shown in the position raised off the receiver on the tool disk;

FIG. 2 is a partially cutaway perspective partial view which shows the area of a receiver on the tool disk and one half of the tool holder which can be attached to this receiver, and

FIG. 3 shows a representation similar to FIG. 2, but a modified embodiment being shown.

FIG. 1, to which reference is made first, shows a peripheral section of a tool disk which is designated as a whole as 1 and which is a component of a tool revolver. Since the other components of the tool revolver which are not shown in this drawing can be of conventional design, a more detailed explanation in this respect is unnecessary. FIG. 1 moreover shows a tool holder which is designated as a whole as 3, shown in the position raised off the tool disk 1, i.e., before mounting on the pertinent receiver of the tool disk 1. The tool holder 3 has a base body 5 which is largely cuboidal with a rectangular outline, on the base body 5 a bottom-side, flat base surface 7 (FIGS. 2 and 3) being present. From the flat top 9 a machining tool 11 which sits in the base body 5 extends up, which in this example is a lathe tool shown highly schematically simplified. As is apparent from FIG. 1, the machining tool 11 is offset out of the central area of the top 9.

The tool disk 1 on its outer periphery conventionally has a plurality of tool stations 13, each of which forms a peripheral side flat surface on the tool disk 1, these surfaces extending parallel to the revolver axis which is not shown. Each of these tool stations 13 has a depression 15 which is rectangular in outline and which is located centrally between unrecessed, lateral mounting surfaces 17 in which there are threaded holes 19 which make it possible to screw down a tool holder 3 which is to be fixed on the pertinent tool station by means of tightening screws 21 which sit in the base body 5 of the holder.

On each tool station 13, for each tool holder 3 which is to be attached, there is a receiver which forms a plate surface 23 which is flat to the top. This plate surface 23 is bordered on both sides along its longitudinal edges by the longitudinal contact surfaces 17 of the tool disk 1. They can project with their top slightly over the top of the plate surface 23 so that the respective tool holder 3 with its base surface 7 on the edge side sits on the indicated contact surfaces 17. Relative to this attachment position, the tool holder 3 can then be attached with its base body 5 via tightening screws 21 as the fastening means on the top of the tool disk 1 in the area of the respective receiver 25. The plate surface 23 largely forms the shape of a rectangular parallelepiped which defines a central longitudinal axis 27 which extends parallel to the revolver axis. Each of these plates 25 can be attached in the pertinent depression 15 by means of a mounting screw 29 which has been countersunk in the flat plate surface 23 in an accurately defined alignment position on the tool disk 1.

The plates 25 on the longitudinal axis 27 lying on the two plate ends each have one fitting body 31 which projects out of the plate surface 23. It has a prismatic shape which is flattened on the top, proceeding from the flat top, oblique fitting flanks 33 diverging from one another extending down to the two sides of the longitudinal axis 27. If the fitting body 31 has crowned oblique fitting flanks 33, line contact with increased adjustment accuracy for the tool holder 3 arises.

As is apparent from the drawings, see in this respect in particular FIGS. 2 and 3, underneath the fitting body 31 on the bottom of each plate 25 there is a clearance 35 which is shown exaggerated in the drawings, formed by the reduction of the thickness of the plate 25 in areas, so that in the plate 25 narrowly limited elastic resilience of the fitting bodies 31 in the direction perpendicular to the plate surface 23 arises. It should be noted that the linear impression or depression grooves 37 can run laterally from the respective fitting body 31. On the whole, spring resilience is formed with a very high spring constant and a correspondingly small spring path, which is preferably in the micron range.

For interaction with the fitting bodies 31, on the base surface 7 of the tool holder 3, there are fitting surfaces which have been recessed in the base surface 7. In the first embodiment shown in FIGS. 1 and 2 they are inside surfaces 39 of each groove 41 which has been machined into the base surface 7 and which is provided specially for each fitting body 31. As is apparent, the groove 41 is open on the end of the base surface 7, has the greatest groove depth and groove width on the open end, and extends, proceeding from the open end, with slightly crowned inside surfaces over a longitudinal area which extends beyond the area of the fitting body 31, the crown of each groove 41 being chosen such that the groove width and groove depth decrease. But a preferred version with grooves which run in a straight line is also possible.

As a result of the interaction of the fitting flanks 33 and the fitting bodies 31, which are elastically resilient with a high spring constant, with the fitting surfaces of the groove 41 of the tool holder 3 which are made in the described manner, an extremely accurately defined positional relationship between the plate 25 which forms the respective receiver on the tool disk 1 and the base body 5 of the tool holder is ensured 3. This means that for positionally defined attachment of the plate 25 to the tool stations 13 of the tool disk 1, which can take place using a calibrated rule, for example a so-called master part, each tool holder 3 which is adjusted with its base body 5 with the plate 25 necessarily assumes the exact, desired setting position so that replacement and/or attachment of the tool holders 3 to the tool disk 1 can take place without more extensive adjustment measures.

FIG. 3 shows one embodiment which differs from the example from FIGS. 1 and 2 only in that instead of separate grooves 41, as are provided in the example described first for each fitting body 31, there is a continuous groove 43 along the longitudinal axis, there being no crowning of the inner surfaces so that in this example flat fitting surfaces are formed which interact with the fitting bodies 31. This embodiment can be advantageously used when absolute position definition along the longitudinal axis is not important for the intended application. If this applies, in this embodiment the advantage can be exploited that feeding of the tool holder 3 for attachment to the receiver of the tool station 13 and taking away of a tool holder 3 which is to be removed from the receiver on the tool disk 1 can take place with a displacement motion along the longitudinal axis 27; this can promote execution of automated tool changing processes.

It should be noted that in order to fix the position of the tool holder 3 in the direction of the longitudinal axis, in the base body 5 of the tool holder 3 there is one blind hole 45 which is open on the base surface, which is offset out of the central area, and which holds a respective pin 47 which projects out of the fastening surface 17 when the tool holder 4 is attached to the tool station 13 so that in this respect a pin fit is implemented. 

1. A tool revolver, in particular for machine tools, having a tool disk (1) which can turn around the revolver axis and which has a plurality of tool stations (13) which are distributed along its periphery and which can be set by turning the tool disk (1) into at least one working position at a time, on at least some of the tool stations (13) there being a receiver (25) for a tool holder (3) and one respective fastening means each being provided in order to fix the respective tool holder (3) on the pertinent receiver (25) in defined positioning, characterized in that for positioning, as an alignment means, there are at least one fitting body (31) which projects out of the receiver (25) and which is elastically resilient perpendicular to it, and fitting surfaces (41; 43) which are recessed in the base surface (7) of the tool holder (3) for interaction with at least one fitting body (31).
 2. The tool revolver according to claim 1, wherein the receiver on the respective tool stations (13) is a plate (25) which is connected to the tool disk (1) and which with its flat surface (23) which lies radially outside relative to the revolver axis borders contact surfaces (17) of the tool disk (1) on both sides, which surfaces extend in the plane parallel to the revolver axis and with which the respectively assignable tool holder (3) with its base surface (7) can be brought into contact.
 3. The tool revolver according to claim 1, wherein the fastening means has clamping means, preferably in the form of a screw union (21) in order to brace the base surface (7) of the tool holder (3) with the respectively assignable contact surface (17) of the tool disk (1).
 4. The tool revolver according to claim 2, wherein the plate (25) largely has the shape of a parallelepiped with a rectangular outline which defines a central longitudinal axis (27) which is parallel to the revolver axis.
 5. The tool revolver according to claim 4, wherein there is one fitting body (31) each on the two ends of the plate (25) on its longitudinal axis (27).
 6. The tool revolver according to claim 5, wherein the fitting bodies (31) have the shape of a prismatic body which is blunt on the top, away from its top to both sides of the longitudinal axis (27) flat fitting flanks (33) diverging from one another extending down and defining planes which are parallel to the longitudinal axis (27) of the plate (25).
 7. The tool revolver according to claim 6, wherein to enable spring resilience of the fitting bodies (31) in the area underneath them between the bottom of the plate (25) and the facing surface of the tool disk (10) there is small clearance (35).
 8. The tool revolver according to claim 5, wherein the fitting surfaces of the respective tool holder (3) which interact with the fitting bodies (31) of the plate (25) are formed by the inner surfaces (39) of at least one groove (41; 43) recessed in the base surface (7) of the tool holder (3).
 9. The tool revolver according to claim 8, wherein the respective groove (41; 43) in the base surface (7) extends over a longitudinal area beyond the area of the respective fitting body (31) and when the tool holder (3) has been mounted on the tool station (13) along the longitudinal axis (27) of the plate (25).
 10. The tool revolver according to claim 5, wherein for each fitting body (31) there is a groove (41) which extends over a partial length of the base surface (7) of the tool holder (3) with a groove base and/or side surfaces (39) which are crowned such that the groove depth and/or groove width proceeding from its open end decreases inwardly.
 11. The tool revolver according to claim 5, wherein there is a groove (43) which has flat fitting surfaces (31) and which is made continuous in the base surface (7) of the tool holder (3) for the two fitting bodies (31).
 12. The tool revolver according to claim 2, wherein the plate (25) which forms the receiver can be mounted on the tool disk (1) by means of a screw union (29) in an exactly defined alignment position which is determined using a rule, especially in the form of a master part.
 13. The tool revolver according to claim 1, wherein the tool holder (3) is positioned along the longitudinal axis (27) using a pin fit (45, 47). 